1. Field of Invention
The tricycle of the invention is in the field of human-powered vehicles.
2. Discussion of Prior Art
U.S. Pat. No. 5,240,267 to Owsen shows a human-powered leaning tricycle. This appears to be the closest prior art to the invention, as front wheel drive is also specified. However, the driver position is not recumbent, but shows instead a somewhat standard upright bicycle riding position. A primary disadvantage of this embodiment is that all of the driver's points of contact, that is, the seat, the handlebars and the pedals, are moving with the leaning front section. In this way, the driver cannot exert a force directly between and including the front and rear sections, whereby accuracy of leaning moments is greatly compromised. Indeed, the driver must shift his/her weight with little hope of correcting an overshift or undershift during a critical turn.
U.S. Pat. No. 3,583,727 to Wallis shows several leaning tricycles. The preferred embodiment is not human-powered. However, one embodiment shown by Wallis is human-powered via pedals. This embodiment is not thoroughly displayed to explain power relayance to a driven wheel and how this affects the overall operation of the vehicle. Additionally, this embodiment also exemplifies the disadvantage noted above where all the driver's points of contact are moving with the leaning front section, resulting in less control of leaning than can be accomplished by the tricycle of the invention. The longitudinal axis of rotation for leaning is well defined as sloping upwardly toward the front of the vehicle thereby imparting a rear steering affect.
U.S. Pat. Nos. 4,469,188 to Mita and 4,541,501 to Kawasaki are nearly identical and show a leaning scooter-like tricycle that is not human-powered. These are cited as showing a similar leaning concept as the tricycle of the invention, whereby a longitudinal axis of rotation is incorporated.
U.S. Pat. No. 4,423,795 to Winchell et al. shows a cambering, also known as leaning, tricycle. The preferred embodiment shown by Winchell et al. is not a human-powered vehicle, but is cited nonetheless as displaying a similar leaning concept to the invention. U.S. Pat. No. 4,325,565 to Winchell shows a leaning, motorized tricycle. U.S. Pat. No. 4,437,535 to Winchell et al. shows a three-wheeled leaning motorcycle. All of these prior art references provide for some control of the amount of lean via foot control of the rear sections. This provides the driver with a direct feel of the rear section. This information of the relative positions and relationship of the front and rear sections provides a desirable control of leaning by the driver as he/she can exert a force between and including the front and rear sections.
All of the above noted prior art shows that the handlebars are attached to the leaning front section. Thus, in no prior art cited is the driver afforded direct control of the amount of lean by way of the hands.
All previous attempts at leaning tricycles noted above have used a low longitudinal axis of rotation--approximating the level of the wheel axles. A disadvantage of this arrangement is the large amount of lateral displacement of the seat upon leaning. Since the driver upon the seat represents a majority of the vehicular mass, this lateral displacement results in a considerable shift of the center of gravity of the vehicle from the midline.
The tricycle of the invention helps to solve many relatively new transportation problems, especially in the urban environment. This may be why prior inventors have not conceptualized the tricycle of the invention to date. The primary factors of traffic congestion and pollution, at their presently high and ever-growing levels, has given rise to the combination of characteristics of human power with a recumbent driver position, high seat placement, and narrow wheelspan. The tricycle of the invention is a zero-emission vehicle that is designed to penetrate traffic as well as a bicycle.
Problems such as traffic congestion, pollution, pedestrian intimidation, social isolation, etc., have developed gradually in the cities of the world and are largely a result of the over-utilization of cars and trucks. The tricycle of the invention contributes greatly to the solution of these relatively new problems.